The correct answer is D. Separation of church and state.
Explanation
In countries like the U.S. it is forbidden for the government to intervene in religious matters, this means the government cannot promote a specific religion or stop citizens from practicing it, therefore religion or church and government are independent which is called separation between the church and the State. This also means the church cannot interfere in religion and therefore no government institution or agency is under clerical or religious order. So, the correct answer is D. Separation of church and state.
